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United States Patent | 5,318,357 |
Colby ,   et al. | June 7, 1994 |
A screw for use in an plasticating injection apparatus includes a plurality of interrupted primary flights. An outer surface of a primary valley is formed by the primary flights and features a plurality of plateaus. The plateaus span adjacent sections of the primary flights and define shallow levels between deeper levels of the primary valleys. This depth differential contributes to a turbulent mixing action which, along with the primary and secondary valleys, contributes to improve mixing action within a metering section of the screw. The primary flights are interrupted by secondary valleys which are of opposite hand to the primary valleys.
Inventors: | Colby; Paul N. (New Castle, PA); Smith; Bradley P. (Youngstown, OH); Bodnar; Shawn P. (East Palestine, OH) |
Assignee: | Spirex Corporation (Youngstown, OH) |
Appl. No.: | 899347 |
Filed: | June 16, 1992 |
Current U.S. Class: | 366/81; 366/90; 366/319; 366/322; 425/208 |
Intern'l Class: | B01F 007/08; B29B 007/42 |
Field of Search: | 425/204,208,209 100/145 366/69,76,77,79,81-85,88-90,96-99,318,319,322-324 198/662,664,665,669,676 |
2335819 | Nov., 1943 | Upton | 198/664. |
3006029 | Oct., 1961 | Saxton | 366/90. |
3564651 | Feb., 1971 | Covington, Jr. et al. | 366/343. |
3652064 | Mar., 1972 | Lehnen et al. | 366/90. |
3687423 | Aug., 1972 | Koch et al. | 425/208. |
3945622 | Mar., 1976 | Sokolow | 366/82. |
3986709 | Oct., 1976 | Vermeulen | 366/90. |
4092015 | May., 1978 | Koch | 425/208. |
4215978 | Aug., 1980 | Takayama et al. | 425/208. |
4639143 | Jan., 1987 | Frankland, Jr. | 366/90. |
4752136 | Jun., 1988 | Colby | 366/323. |
4779989 | Oct., 1988 | Barr | 425/208. |
4840492 | Jun., 1989 | Nakamura | 366/81. |
4846659 | Jul., 1989 | Nakamura | 425/208. |
4944906 | Jul., 1990 | Colby et al. | |
4953279 | Sep., 1990 | Colby. | |
4963033 | Oct., 1990 | Huber et al. | 366/81. |
5018917 | May., 1991 | Colby. | |
5033860 | Jul., 1991 | Nakamura | 366/90. |
5035509 | Jul., 1991 | Kruder | 425/208. |
5071256 | Dec., 1991 | Smith et al. | 366/89. |
Foreign Patent Documents | |||
2908497 | Sep., 1980 | DE | 425/208. |
5546304 | Nov., 1980 | JP | 425/208. |
Screw Design Efficiency in Color Distributive Mixing with ABS Resins by Barbara Furches and John Bozzelli (Article reprinted from ANTEC '87). Implementation of Advanced Screw Design for Injection Molding. How to Improve Your Productivity and Profits: A Case History by J. Bozzelli and B. Larin (Reprinted from ANTEC '90). Advanced Screw Design Applied To Semi-Crystalline Thermoplastic Resins by M. P. Sepe (Reprinted from ANTEC '91). Screw and Barrel Technology-SPIREX by Paul N. Colby (1985). |